Apparatus and method for subcutaneous electrode insertion

Abstract

Devices and methods for electrode implantation. A first embodiment includes an electrode insertion tool adapted to tunnel through tissue and attach, at its distal end, to a lead, such that the lead may be pulled into the tunneled space as the electrode insertion tool is removed. Additional embodiments include methods for inserting electrode/lead assemblies, including a method wherein an insertion tool is first used to tunnel through tissue, then to pull an electrode/lead into the tunneled space. In a further embodiment the insertion tool is next used, with a splittable sheath disposed thereon, to create an additional path into tissue, after which the insertion tool is removed, leaving the sheath in place; a lead is inserted to the sheath, and, finally, the splittable sheath is removed over the lead.

1. A method of inserting a lead electrode assembly subcutaneously into a patient, the method comprising:
 making a first incision; 
 making a second incision spaced from the first incision; 
 advancing a tool having proximal and distal ends through the first incision toward the second incision, the distal end of the tool being adapted for dissecting tissue, wherein the tool is advanced by dissecting tissue with the distal end of the tool; 
 securing the lead electrode assembly to the tool near the distal end of the tool near the second incision; 
 withdrawing the tool through the first incision such that the lead electrode assembly is pulled into the patient through the second incision via a first subcutaneous path; 
 advancing the tool along a second subcutaneous path through the first incision toward a chosen subcutaneous location; 
 withdrawing the tool from the second subcutaneous path; and 
 inserting a length of the lead electrode assembly that has been passed into the patient through the second incision and toward the first incision via the first subcutaneous path along the second subcutaneous path: 
 wherein: 
 during the step of advancing the tool from the first incision toward the second incision, a splittable sheath is secured onto the tool; 
 during the step of withdrawing the tool through the first incision such that the lead electrode assembly is pulled into the patient through the second incision, the splittable sheath continues to be secured onto the tool; 
 during the step of advancing the tool along the second subcutaneous path through the first incision toward the chosen subcutaneous location, the splittable sheath is disposed over the tool; 
 during the step of withdrawing the tool from the second subcutaneous path, the splittable sheath is retained in place along the the tool, the splittable sheath is retained in place along the second subcutaneous path and is no longer secured to the tool; and 
 the step of inserting the length of lead electrode assembly along the second subcutaneous path includes the length of lead electrode assembly along the path includes advancing a distal end of the lead electrode assembly into the splittable sheath. 
 
     
     
       2. The method of  claim 1 , wherein:
 the first incision is along the patient's sternum relatively near the patient's median plane; and 
 the second incision is laterally spaced from the first incision. 
 
     
     
       3. The method of  claim 1 , wherein:
 the first incision is along the patient's sternum relatively near the patient's median plane; 
 the second incision is laterally spaced from the first incision; and 
 the chosen subcutaneous location is located cephalic of the first incision. 
 
     
     
       4. The method of  claim 1 , further comprising the step of removing the splittable sheath from the second subcutaneous path while maintaining the length of the lead electrode assembly at least partly in a position along the second subcutaneous path. 
     
     
       5. The method of  claim 1 , wherein the tool is configured to enable fluid infusion therethrough, the method further including infusing a fluid into the patient with the tool. 
     
     
       6. The method of  claim 5 , wherein the fluid is a local anesthetic. 
     
     
       7. The method of  claim 5 , wherein the fluid is a tissue adhesive. 
     
     
       8. The method of  claim 1 , wherein the tool includes an attachment feature near its distal end, wherein the step of securing the lead electrode assembly to the tool includes using the attachment feature to attach to the lead electrode assembly. 
     
     
       9. The method of  claim 8 , wherein the attachment feature includes a suture hook, wherein the step of securing the lead electrode assembly to the tool includes securing a suture to the suture hook. 
     
     
       10. The method of  claim 8 , wherein the attachment feature includes a suture hole, wherein the step of securing the lead electrode assembly to the tool includes passing a suture through the suture hole and thereby securing the suture to the tool. 
     
     
       11. The method of  claim 10 , wherein the tool includes a fluid infusion lumen therethrough, the fluid infusion lumen opening into the suture hole, the method further comprising infusing a fluid into the patient through the fluid infusion lumen. 
     
     
       12. The method of  claim 8 , wherein the attachment feature includes a groove enabling a suture to be attached to the tool, wherein the step of securing the lead electrode assembly includes attaching a suture to the tool using the groove. 
     
     
       13. A method of subcutaneously inserting a lead electrode assembly into a patient comprising:
 making a first incision in the patient's torso; 
 making a second incision in the patient's torso; 
 providing a tool having proximal and distal ends with a splittable sheath disposed thereon; 
 advancing the tool and sheath through the first incision toward the second incision; 
 advancing the distal end of the tool through the second incision; 
 securing the lead electrode assembly to the distal end of the tool; 
 withdrawing the tool through the first incision such that the lead electrode assembly is pulled into the patient through the second incision, and 
 pulling the lead assembly through the first incision until a first length of the lead assembly extends out of the first incision; 
 wherein the method includes retaining the splittable sheath in a fixed position on the tool at least until a portion of the lead electrode is drawn through the first incision. 
 
     
     
       14. The method of  claim 13 , further comprising:
 after pulling the lead assembly through the first incision until a first length of the lead assembly extends out of the first incision, advancing the tool and sheath through the first incision to a chosen subcutaneous location spaced from both the first incision and the second incision, creating a subcutaneous path from the first incision to the chosen subcutaneous location; 
 withdrawing the tool while maintaining the splittable sheath in place; 
 advancing the first length of the lead assembly into the sheath; and 
 withdrawing the sheath while maintaining the first length of the lead assembly in place in the subcutaneous path. 
 
     
     
       15. The method of  claim 14 , wherein the step of withdrawing the sheath includes splitting the sheath along an axial line of weakness. 
     
     
       16. The method of  claim 13 , wherein the tool is configured to enable fluid infusion therethrough, the method further including infusing a fluid into the patient with the tool. 
     
     
       17. The method of  claim 13 , wherein the tool includes an attachment feature near its distal end, wherein the step of securing the lead electrode assembly to the tool includes using the attachment feature to attach to the lead electrode assembly. 
     
     
       18. The method of  claim 17 , wherein the attachment feature includes a suture hook, wherein the step of securing the lead electrode assembly to the tool includes securing a suture to the suture hook. 
     
     
       19. The method of  claim 17 , wherein the attachment feature includes a suture hole, wherein the step of securing the lead electrode assembly to the tool includes passing a suture through the suture hole and thereby securing the suture to the tool. 
     
     
       20. The method of  claim 19 , wherein the tool includes a fluid infusion lumen therethrough, the fluid infusion lumen opening into the suture hole, the method further comprising infusing a fluid into the patient through the fluid infusion lumen. 
     
     
       21. The method of  claim 17 , wherein the attachment feature includes a groove enabling a suture to be attached to the tool, wherein the step of securing the lead electrode assembly includes attaching a suture to the tool using the groove.